Winter Storm Watch 1, NWS Jackson, MS

122 
WWUS44 KJAN 100447
WSWJAN

URGENT - WINTER WEATHER MESSAGE
National Weather Service Jackson MS
1047 PM CST Sat Jan 9 2021


LAZ007>009-015-016-023-MSZ035-040>042-047-101400-
/O.CON.KJAN.WS.A.0001.210111T0300Z-210111T1500Z/
Morehouse-West Carroll-East Carroll-Richland-Madison LA-
Franklin LA-Humphreys-Issaquena-Sharkey-Yazoo-Warren-
Including the cities of Bastrop, Oak Grove, Epps, 
Lake Providence, Rayville, Delhi, Tallulah, Winnsboro, Belzoni, 
Isola, Mayersville, Rolling Fork, Anguilla, Yazoo City, 
and Vicksburg
1047 PM CST Sat Jan 9 2021

...WINTER STORM WATCH REMAINS IN EFFECT FROM SUNDAY EVENING
THROUGH MONDAY MORNING...

* WHAT...Total snow accumulations of two to three inches, with 
  locally higher amounts, are possible. 

* WHERE...Portions of northeast Louisiana and western 
  Mississippi. 

* WHEN...From Sunday evening through Monday morning.

* ADDITIONAL DETAILS...Plan on difficult travel conditions, 
  including during the morning commute on Monday. Brief power 
  outages are possible. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Watch means there is a potential for significant
snow, sleet, or ice accumulations that may impact travel.
Continue to monitor the latest forecasts.

&&

$$

891 
WWUS44 KJAN 100952
WSWJAN

URGENT - WINTER WEATHER MESSAGE
National Weather Service Jackson MS
352 AM CST Sun Jan 10 2021


LAZ007>009-015-016-023-MSZ035-040>042-047-101800-
/O.UPG.KJAN.WS.A.0001.210111T0300Z-210111T1500Z/
/O.NEW.KJAN.WS.W.0001.210111T0300Z-210111T1800Z/
Morehouse-West Carroll-East Carroll-Richland-Madison LA-
Franklin LA-Humphreys-Issaquena-Sharkey-Yazoo-Warren-
Including the cities of Bastrop, Oak Grove, Epps, 
Lake Providence, Rayville, Delhi, Tallulah, Winnsboro, Belzoni, 
Isola, Mayersville, Rolling Fork, Anguilla, Yazoo City, 
and Vicksburg
352 AM CST Sun Jan 10 2021

...WINTER STORM WARNING IN EFFECT FROM 9 PM THIS EVENING TO NOON
CST MONDAY...

* WHAT...Total snow accumulations of two to four inches, with
  locally higher amounts, are expected.

* WHERE...Portions of northeastern Louisiana and western 
  Mississippi. 

* WHEN...From Sunday evening through Monday morning.

* ADDITIONAL DETAILS...Plan on difficult travel conditions,
  including during the morning commute on Monday. Brief power
  outages are possible. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning means significant amounts of snow or 
sleet are expected or occurring. This will make travel very 
hazardous. Continue to monitor the latest forecasts.

&&

$$

ARZ074-075-LAZ025-MSZ034-036-101800-
/O.NEW.KJAN.WS.W.0001.210111T0300Z-210111T1800Z/
Ashley-Chicot-Tensas-Washington-Holmes-
Including the cities of Crossett, North Crossett, Hamburg, 
West Crossett, Dermott, Lake Village, Eudora, Newellton, 
St. Joseph, Waterproof, Greenville, Durant, Tchula, Lexington, 
Pickens, and Goodman
352 AM CST Sun Jan 10 2021

...WINTER STORM WARNING IN EFFECT FROM 9 PM THIS EVENING TO NOON
CST MONDAY...

* WHAT...Total snow accumulations of two to four inches, with
  locally higher amounts, are expected.

* WHERE...Portions of northeastern Louisiana, central Mississippi,
  and southeastern Arkansas.

* WHEN...From Sunday evening through Monday morning.

* ADDITIONAL DETAILS...Plan on difficult travel conditions,
  including during the morning commute on Monday. Brief power
  outages are possible. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Storm Warning means significant amounts of snow or 
sleet are expected or occurring. This will make travel very 
hazardous. Continue to monitor the latest forecasts.

&&

$$

LAZ024-026-MSZ018-019-025>033-037-038-043>045-048>050-053-054-059-
060-101800-
/O.NEW.KJAN.WW.Y.0001.210111T0300Z-210111T1800Z/
Catahoula-Concordia-Bolivar-Sunflower-Leflore-Grenada-Carroll-
Montgomery-Webster-Clay-Lowndes-Choctaw-Oktibbeha-Attala-Winston-
Madison MS-Leake-Neshoba-Hinds-Rankin-Scott-Claiborne-Copiah-
Jefferson-Adams-
Including the cities of Jonesville, Harrisonburg, Vidalia, 
Ferriday, West Ferriday, Cleveland, Indianola, Ruleville, 
Greenwood, Grenada, Vaiden, North Carrollton, Carrollton, Winona,
Eupora, Mathiston, West Point, Columbus, Ackerman, Weir, 
Starkville, Kosciusko, Louisville, Ridgeland, Madison, Canton, 
Carthage, Philadelphia, Pearl River, Jackson, Pearl, Brandon, 
Richland, Forest, Morton, Port Gibson, Crystal Springs, 
Hazlehurst, Wesson, Fayette, and Natchez
352 AM CST Sun Jan 10 2021

...WINTER WEATHER ADVISORY IN EFFECT FROM 9 PM THIS EVENING TO
NOON CST MONDAY...

* WHAT...Total snow and sleet accumulations of up to two inches,
  with locally higher amounts, are possible.

* WHERE...Portions of central Louisiana and central Mississippi.

* WHEN...From Sunday evening through Monday morning.

* ADDITIONAL DETAILS...Difficult travel conditions, including
  during the morning commute on Monday, are possible especially on
  bridges and overpasses.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Winter Weather Advisory means that periods of snow, sleet, or 
freezing rain will cause travel difficulties. Be prepared for 
slippery roads and limited visibilities, and use caution while 
driving.

&&

$$

DL

Area Forecast Discussion...UPDATED
National Weather Service Jackson MS
1204 PM CST Sat Jan 9 2021

.UPDATE...
Updated for 18Z aviation discussion

&&

.AVIATION...
18Z TAF discussion:
VFR stratus deck still covered north and cntrl portions of the
area. VFR conditions are still expected across most TAF sites but
cigs may lower to MVFR at GWO and GTR this aftn before briefly
improving this evening. VFR conditions are expected to continue
Sunday morning at most TAF sites but MVFR cigs may develop in the
north again by 17Z. /22/

&&

.DISCUSSION...
Visible satellite imagery showed a layer of stratus covering the
northeast half of our CWA that was continuing to erode from the
southwest but latest models suggest clouds will increase from the
west this afternoon. Surface analysis showed a center of high
pressure to our north. The resulting cool north wind beneath the
cloud cover will hold afternoon highs well below normal. Other
than adjusting cloud cover in spots, the forecast was on track.
/22/

Prior discussion below:

Today and tonight: While a pesky low cloud deck has persisted
across much of the area overnight, we have seen some encouraging
signs as it has begun to erode on the south and west sides and
ceilings have slightly increased. Looking ahead to today, the main
question is to what extent the clouds will stick around and what
impact that might have on temperatures. With low level flow
remaining somewhat convergent over the northeastern portion of the
area, I suspect that's where clouds will be most pesky through
the day. Some high res guidance has even hinted at a few snow
flurries developing in that regime, though confidence in this is
too low to mention in the forecast for today, and even if it did
materialize from the shallow moist layer that remains, it would
certainly not be measurable. As flow becomes more anticyclonic
this afternoon, at least some breaks should become more common.
Still, weak to moderate cold advection will persist through the
day, so while highs are expected to be a few degrees warmer than
yesterday, it will still be a rather cool day with wind chills
struggling to get out of the 30s over the northern half of the
area. A gradient toward higher max temps will be favored for the
areas farther south and west which are expected to see more sun.
For tonight, while lesser lower cloud cover is expected, high
clouds will begin to increase overnight ahead of the next system.
Still, with winds slacking off more, it should be a cold night
with lows in the 20s common. /DL/

Sunday through Saturday:

A strong shortwave trough will swing through the Rio Grande Valley
on Sunday. Height falls overspreading a coastal baroclinic zone will
help induce surface cyclogenesis over the Texas coast with the low
sliding east along the Gulf Coast Sunday night into Monday.
Meanwhile, a continental polar airmass and sprawling surface high
will remain entrenched across the Great Plains and into the Lower
Mississippi Valley, which will set the stage for a wintry weather
episode across portions of the forecast area. Moisture will
overspread the cold airmass from west to east Sunday night into
Monday morning with precipitation continuing into the afternoon
hours. Precipitation will likely start as a rain/snow mix with a
changeover to predominately snow northwest of the Natchez Trace
corridor. A transition zone of rain/snow will setup somewhere along
the Natchez Trace, but exact placement remains elusive and will be
difficult to nail down until about 24-36 hours out from the event.
Further southeast, guidance is in better agreement on warmer thermal
profiles with precipitation remaining predominately a sad, cold rain.

Confidence continues to increase that northwest portions of the area
will see accumulating snowfall. However the big questions are 1) how
much snow will accumulate, and 2) where will the rain/snow line end
up. The main issue in the models right now is a complex of
thunderstorms over the northern Gulf of Mexico and its possibility
to inhibit moisture transport poleward. As such, spread still
remains in the guidance as to whether higher QPF will be realized
further north and juxtaposed with the coldest air. Regardless,
strong ascent associated with the mid-level trough and collocated
within the dendritic growth zone will be sufficient for snowfall
totals to approach the 2-3" range over northeast Louisiana and west
central Mississippi. Locally higher amounts will also be possible if
mesoscale snow banding aided by mid-level frontogenesis is realized.
A winter storm watch may be needed if this continues to hold true.
Up to 2" of snow will be possible across the limited threat area
along the Natchez Trace corridor and over the Upper Delta.

The greatest uncertainty exists along the Trace corridor as this is
where the rain/snow line will be. Furthermore, a sharp snowfall
gradient is expected and will further add to forecast uncertainty
across the transition zone. This will be key for the Jackson metro
as the rain/snow line wavers through the area. It is looking more
and more possible that the metro area may see a mix of rain/snow
with only small accumulations possible. All it will take for higher
amounts though is for slightly cooler boundary layer temperatures
and dynamic cooling from higher precip rates to push the rain/snow
line further south. Further adjustments will be made to the forecast
through the weekend so check back for the latest information.

As for the rest of next week, the clouds will finally move out
Monday night into Tuesday. Radiational cooling will allow temps to
bottom out in the mid to upper 20s for a cold Tuesday morning.
Heights will be on the rise then and temperatures will follow so
that highs will rise into the upper 40s to near 50 Tuesday
afternoon. Another shortwave trough is expected to move through the
region on Wednesday and finally kick out the cold continental polar
airmass. Conditions will return to near normal for this time of year
then with highs in the 50s and lows in the 30s through the rest of
the week.
/TW/10/

&&

.PRELIMINARY POINT TEMPS/POPS...
Jackson       44  26  46  32 /   0   0   0  75
Meridian      44  25  47  31 /   0   0   0  59
Vicksburg     45  27  45  31 /   0   0   3  83
Hattiesburg   49  26  49  32 /   0   0   0  71
Natchez       48  28  47  33 /   0   0   5  89
Greenville    41  28  41  31 /   0   0   1  63
Greenwood     42  27  44  31 /   0   0   0  57

&&

.JAN WATCHES/WARNINGS/ADVISORIES...
MS...None.
LA...None.
AR...None.

&&

TW/10/DL/22

Hazardous Weather Outlook
National Weather Service Jackson MS
404 AM CST Sat Jan 9 2021

ARZ074-075-LAZ007>009-015-016-023>026-MSZ018-019-025>066-072>074-
101015-
Ashley-Chicot-Morehouse-West Carroll-East Carroll-Richland-
Madison LA-Franklin LA-Catahoula-Tensas-Concordia-Bolivar-
Sunflower-Leflore-Grenada-Carroll-Montgomery-Webster-Clay-Lowndes-
Choctaw-Oktibbeha-Washington-Humphreys-Holmes-Attala-Winston-
Noxubee-Issaquena-Sharkey-Yazoo-Madison MS-Leake-Neshoba-Kemper-
Warren-Hinds-Rankin-Scott-Newton-Lauderdale-Claiborne-Copiah-
Simpson-Smith-Jasper-Clarke-Jefferson-Adams-Franklin MS-Lincoln-
Lawrence-Jefferson Davis-Covington-Jones-Marion-Lamar-Forrest-
404 AM CST Sat Jan 9 2021

This hazardous weather outlook is for portions of southeast
Arkansas, northeast Louisiana, central Mississippi, north central
Mississippi, and south central Mississippi.

.DAY ONE...Today and Tonight

The probability for widespread hazardous weather is low.

.DAYS TWO THROUGH SEVEN...Sunday through Friday

A weather system is expected to combine with cold air to bring
the accumulating snow to northwest portions of the  ArkLaMiss
region Sunday night into Monday. Snowfall totals up to 3" with
locally higher amounts are possible. This will lead to a threat
for hazardous travel conditions and the possibility for a few
downed trees and power lines.

(https://www.weather.gov/images/jan/graphicast/1.png

.SPOTTER CALL TO ACTION STATEMENT...
The activation of storm spotters, HAM radio operators, and
emergency management personnel in support of severe weather
operations is not expected through next Friday.

10

&&

...HAZARD LEGEND...

No short term hazards expected.

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